1968 Ouachita Transom Wood Replacement

[AndyN]

Recently picked up a 16' 1968 Ouachita jon boat. Tore into the transom last night and it was much worse than expected. One of the previous owners put a steel plate over the wood to strengthen it and didn't seal the bolts going through the transom. This let water in and eventually rotted the wood. I got everything off last night and now I've got a few questions. I've settled on ACX plywood that I can get locally but I'm torn on how to treat it. The wood is about 60" across the top and 12" deep. If I go the epoxy route how much will I need to coat this? My other option is "old timers formula". Then I'll paint with oil based paint after sealing. For fasteners I'm assuming stainless with nylon washers and sealed with 5200 is the best option? I'll probably use stove bolts to replace the rivets going through the hull on the knee braces.

 

[LDUBS]

I had the same question for a project I did a couple weeks ago. It wasn't boat related, though that should'nt matter because the 1/2" ply doesn't know the difference. I covered about 22 sq ft. I bought a quart of 2:1 saturating epoxy resin. I have at least half that left. I thought I laid it on pretty thick. It is good to not to mix up more than you can apply before it starts to fasten up. I mixed 4 ounces of resin with 2 ounces of hardener to begin. That amount worked pretty well.

 

[DaleH]

I too was going to recommend a quart (total) kit too, and likely you’ll have much left over. But seal the edges grains really well, so I do a couple coats on that, adding the new coats once the previous coats kick, i.e., are tacky to the touch.

Look up www.raka.com & call Larry or Mike and they will tell you exactly how much you may need. They might even tell you that their $22 sample kit will do what you need!

As far as mixing up epoxy, DO NOT MIX up too much all at once! The heat it generates from curing will make the whole thing ‘cook off’ and I have seen containers almost catch on fire, smoking like you cannot believe! I have seen plastic mix containers melt away and cause a mess in the boat too!

In my signature, look up how I prepped the wood for the SS through bolts, in the 15’ StarCraft.

 

[wmk0002]

I too was going to recommend a quart (total) kit too, and likely you’ll have much left over. But seal the edges grains really well, so I do a couple coats on that, adding the new coats once the previous coats kick, i.e., are tacky to the touch.

Look up www.raka.com & call Larry or Mike and they will tell you exactly how much you may need. They might even tell you that their $22 sample kit will do what you need!

As far as mixing up epoxy, DO NOT MIX up too much all at once! The heat it generates from curing will make the whole thing ‘cook off’ and I have seen containers almost catch on fire, smoking like you cannot believe! I have seen plastic mix containers melt away and cause a mess in the boat too!

In my signature, look up how I prepped the wood for the SS through bolts, in the 15’ StarCraft.

Dale, do you recommend doing a coat, letting tack up, then re-coating as opposed to letting one coat fully cure then sanding/cleaning and applying a second coat?

 

[DaleH]

do you recommend doing a coat, letting tack up, then re-coating as opposed to letting one coat fully cure then sanding/cleaning and applying a second coat?

Great question! I only do the multiple coats on the edge grains. By applying before the other coat has cured ensures a chemical bond with the next coat.

I honestly have never done (nor have ever need to do) more than 1 coat on the wood panels, unless I am laminating 2 of them together with glass in-between. Then I will sand/clean each side to be laminated, before applying the glass & new resin.

Some epoxy mixes need to have any ‘amine blush’ that occurs from the curing process sanded and cleaned off well prior to the next coat.

 

[wmk0002]

do you recommend doing a coat, letting tack up, then re-coating as opposed to letting one coat fully cure then sanding/cleaning and applying a second coat?

Great question! I only do the multiple coats on the edge grains. By applying before the other coat has cured ensures a chemical bond with the next coat.

I honestly have never done (nor have ever need to do) more than 1 coat on the wood panels, unless I am laminating 2 of them together with glass in-between. Then I will sand/clean each side to be laminated, before applying the glass & new resin.

Some epoxy mixes need to have any ‘amine blush’ that occurs from the curing process sanded and cleaned off well prior to the next coat.

Thanks! That's good to hear as that will be less work, time, and resin lol.

 

[AndyN]

Thanks for the tips. The only reason I ask about using nylon washers is any reaction that may occur from the steel coming in contact with the aluminum. Or will the layer of 5200 be sufficient?

 

[DaleH]

The only reason I ask about using nylon washers is any reaction that may occur from the steel coming in contact with the aluminum. Or will the layer of 5200 be sufficient?

Personally I'd NEVER use a tin in saltwater without separating the tin from the stainless steel, as for galvanic corrosion, saltwater is an ideal electrolyte. But to your question, here is what 5200 does to unprotected or unprimed tin.

If I only boated in freshwater ... well, that would be your decision to make, as would take a loooooong time to have any ill effect I'd guess, without any isolation.

.....


.....
Now on my 1989 hull, always used in saltwater, I had placed nylon washers under the SS bolt heads and I just had to remove some on the transom, so you know they get splashed with saltwater. I had ZERO evidence of corrosion around the bolt head and no crevice corrosion on the SS bolt body. Works for me!

But granted, I readily admit I tend to go towards 'overkill', but again ... I expressly use my tins in the salt.

 

[AndyN]

If I end up in salt water in KS we've got a serious problem. I got my Raka epoxy ordered yesterday and I'm picking up wood Friday. Fastenal should have everything else I need. If all goes smoothly I should be posting an update in the next couple of weeks.